Folding machine



.May 24, 1949. l.. R. DICKENSON 2,470,762

FOLDING MACHINE Filed April 25, 1947 5 Sheets-Sheet l .9 INVENTOR.

Leo R. Dickenson May 24, 1949. R. DlcKl-:NsoN v2,470,762

v FOLDING MACHINE l Y Filed April 25, 1947 5 Sheets-Sheet 2 INVENTOR. Leo R. Dickenson May 24, 1949.

L. R. DICKENSON FOLDING MACHINE 5 sheets-sheet 5 Filed April 25, 1947 INVENTOR.` Leo R. Dickenson L. R. DICKENSON 1 FOLDING MACHINE May 24, 1949.

5 Sheets-Sheet 4 Filed April 25, 1947 INVENTOR.

Leo R. 4Dickemfon May 24, 1949. 1 R. DlcKENsoN f 2,470,752

FLDINGMAGHINE Filed April 25. x94? 5 ShewS-S'he'l 5v ,INVENTolL Leo R. Drake mon Patented May 24, 1949 UNITED .STATES P TENT OFFICE (Granted under theA act of March 3, 1883, as amended April v30, 1928; .370 0. G. 757) 4 Claims.

The invention described herein may be manufactured and used by .or for the Government .of the United States for AGovernmental purposes without the payment to me of any royalty thereon inl accordance with the provisions ofthe ,act of April 30, 1928 (Ch. 460, 46y Stat. L. 467).

This invention relates to folding machines and more particularly to improvements in sheet foldingmachines of the drop knife type.

This invention is particularly useful lin a, conventional sheet folding machine having a plurality of drop knives which operate in succession on a sheet of paper or like` material passing through the machine to provide a plurality of folds in the sheet in the .productionof assignature or folded form. ,It is, therefore, appropriate to explain the present invention in its application to such machine.

In .these conventional folding machines sheets are fed therethrough in successionandfrom folding station to folding station. The sheet feeding mechanism usually includes moving tapes and rollers as well as the drop knives. All operating parts vof the machine are driven by asingle motor; usually an electric motor. It frequently happens that a number of sheets accidentally become jammed or balled up in the feedingmechanism forany one of va number of reasons. Asa result,.

much time and effort are wasted in removingthe fouled sheets and restoring the machine to.

normal operation. Fouling of the sheets may also cause damage tothe machine and necessitate costly repairs. At the same time, there is a loss in production of signatures by the machine.

This invention provides the `Yfolding.' machine with a device which operates to stopvthefmachinre.

in event a sheet fails to reach proper position at a station below a folding knife-and which permits the machine tocontinue its normal operations-as longas sheets are properly passingtherethrough.

It is therefore an object of this invention vto improve sheet folding machines.

Another Objectis to provide a sheet -folding machine with an automatically operating. device for interrupting the operation of the motorwhich drives the machine in the event a sheet .fails-to movenormally through the machine.

Still another object is to provide. sheet-folding machines with a safety devicewhich is offrelatively simple and rugged'construction, yis inexpensive tomanufacture, ishighly efficient forits intended purpose, and will minimize production losses.

Other objects and advantages will be apparent from fthe-.following description, .the .appended claims and the accompanying drawings which illustrate a preferred embodiment ofv this invention.

Referring to the drawings,

Fig. 1 is a topfplan view of the second folding stationvofa multifolding machine, equipped with a preferred embodiment of this invention.

Fig. 2 is a side view, partly in elevation and partlyin crossfsection of the constructionof Fig. 1. Fig. 2 .also shows the wiring of theswitch forming part of the safety device of this invention.

Figs..` 1 and 2 .show a once-folded sheet con- 4A tactingthe safety device trip plate and in .posi-` .l tion for a perforating operation.

Figs. 43 throught' are similar to Fig. 2, and show the operationof the safety device.

Fig. 3 shows the setting of the machine rand the safetydeviceat the time a once-.folded and .perforatedsheet is in position for a secondifoldl ing operationf the perforating blade andthe foldV ing'knifenovv being in elevated positions.

Fig; 4 shows the folding knife inav lowered. folding position,a sheet in the processof receiv- :ing its second fold, and the safety device `in a corresponding setting.

Figshowsithe setting of the machinev and the safetydevice when either a once-folded shcetais about tobe fedto the secondfolding station for -aperfcrating operation, or asheet has failed to be properly advanced to perforating position, at=v thersecondvfolding station and into proper engagement with the safety device trip plate.

Fig. 6 shows the setting of the machine and Vthe safety device which follows the setting .of

Fig. 5 ineventa sheet has Afailed-.tope properly advanced to perforating position at the second folding station and into proper engagement with the safety device trip plate. The safety device switchis in the open circuit. position,-the

machine motor is deenergized, andthe vfolding;

knife has returned to its uppermostposition. Fig. 7 is a detail View taken online l-leof Fig. land shows the supporting guide kbar and itsfreciprocating.Y mechanism in theshe'et'perfo f rating position.

Fig.y 8- correspondstoFig`- '7, but shovvsdahe.bar`v andthe-mechanism in the sheet folding-position.

Figs. :9 :and 10 are respectively side and front" views of a detail of the safety device of iFigs. :1 through 6. Fig-9 showsindottedlinesa'second setting Hof the safety :device trip. plate.l andzpawl.

For` ,the `purpose of illustrating a .preferredif emboidimentofthis invention, it isillustrated in the; Adrawings as .applied tov the .second folding station of a conventional multi-folding machine for producing signatures of folded forms of sheets fed to and through the machine in succession and at regular machine-controlled intervals. A sheet s passing from the iirst folding station (not shown) to the second folding station has a fold at its leading edge (see Fig. 2) and is fed by tapes (not shown). These tapes and all driven parts of the machine derive their power from the shaft 5 of an electric motor I (see Fig. 2) according to conventional practice.

The folded sheet s is fed (see Figs. 1 and 2) over` and on a slotted perforator bar 2, spaced folding guide bars 3, and paper supporting rods 4. Forward movement of the folded sheet s is arrested by guide clips 6 (see Fig. l), which are suitably mounted on and secured to a supporting guide bar 1.

The folded sheet s, now in the position illustrated in Figs. l and 2, is ready for a perforating operation, in which a perforating blade 8 is lowered from its Fig. 2 position, passes through the folded sheet s and the slotted perforator bar 2, and returns to its Fig. 2 position. The perforating blade 5 at its ends is secured to the uprights 9 which are vertically reciprocate'd by the shaft 5 of the motor i through conventional mechanism (not shown).

The sheet s-now perforated-is shifted or advanced from the perforating position (Figs, l and 2) to the next (second) folding position (Fig. 3) by conventional grippers Il (Fig. 1) according to conventional practice. The grippers II are supported by and secured to the supporting bar 1 similarly to the guide clips I5 (Fig. 1).

Movement of the bar 1 with its guide clips ii and the grippers II is provided by mechanism shown in Figs. 1, 2, 7 and 8. The guide bar 1 is` adjustably supported in conventional manner by two adjusting fingers I2, each of which has threaded engagement with a guide adjusting screw I3. Each screw I3 is supported by and axially shiftable through a bearing It and a box I6, both of conventional construction and secured to a stationary machine frame member I1. A hand wheel I8 on the adjusting screw I3 is provided for its adjustment. Each screw I3 is axially shifted from a forward (perfcrating) position (Fig. 7) to a retracted (folding) position (Fig. 8) and vice versa by the conventional mechanism of Figs. '1 and 8 which comprises a Cam ZI driven from the shaft 5 of the motor I, a bell crank lever 22, a link 23, and a two-arm lever 24.

The sheet s now having been folded once and also perforated, is ready for the second folding operation (see Fig. 3). A drop folding knife 2t is lowered to engage the folded sheet s along its line of perforations and to fold the sheet s by passing it through the slot between the spaced folding guide bars 3 and into engagement with the folding rollers 21 (Fig. 2). These rollers 21 pass the twice folded sheet S to the folding rollers 28, which in turn feed the sheet s to tapes (not shown) that pass the sheet to a third folding station (not shown). The drop knife 26 is secured at its opposite ends to uprights 29 which derive their vertical reciprocating motion from the shaft 5 of the motor I through conventional mechanism (not shown). Conventional mechanism (not shown) also transmits the drive of motor shaft 5 to the rollers 21 and 28.

The motor I (Fig. 2) is connected by Wiring 3l to any available and convenient source of electric power. A switch, such as a double pole switch 32, may be provided in the motor circuit formed '4 by the wiring 3l. When the switch 32 is placed in circuit closing position, the motor I is energized and provides the drive for the folding machine.

Safety device The safety device includes a trip plate or member 4i, which is pivotally supported and weighted to normally rest in an inclined position (Figs. 4, 5, 6, and 9) and to be shifted by an advancing sheet s to a vertical position (Figs. l, 2, 3 and 9). In its inclined position, the trip plate 4I is disposed in the path of an advancing sheet s. In its vertical position, the trip plate fil cooperates with the guide clips ii to position properly the leading folded edge of the sheet s.

The trip plate di is pivotally secured at its opposite sides to the outer ends of two arms 42, which at their inner ends are secured to a bracket member 43. The bracket member 43 is mounted on and secured to the guide bar 1 in any suitable and conventional manner.

The trip plate 4I is provided with a fixed pin Il that extends through an opening in the bracket member d3 for engagement with a pawl 4G pivotally secured to the bracket member 43 (Fig. 9). In the inclined position of the trip plate 4I, its pin i4 frees the pawl 46 for operative engagement with a ratchet bar i1 (see Figs. 4, 5, 6 and 9). in the vertical position of the trip plate Si, it has face to face contact with the bracket member 43 (see Fig. 9), and the pin 44 positions the pawl 45 so that it is free of engagement with the ratchet bar 41 (see Figs. 2, 3 and 9).

The ratchet bar l1 extends through an opening 50 in the bracket member 43 and slidably rests on the bottom edge of such opening 5D (see Fig. 10). The lower end of the trip plate 4I is bifurcated to permit free longitudinal or end-wise movement of the ratchet bar 41 (See Fig. 10).

The ratchet bar i1 at one end is supported from one end of a spring arm 48. The other end of the spring arm 48 is supported by and secured to the machine frame member I1. The arm 48 is adapted normally to position the ratchet bar 41 in its idle position (see Fig. 2, for example), but yields to permit the ratchet bar 41 to be aclvanced to the open circuit position of Fig. 6 by the pawl 45 during movement of the supporting guide bar 1 from the Fig. 2 position to the Fig. 6 position. rIhe resiliency of the spring arm 43 is effective to restore the ratchet bar 41 to the Fig. 2 position upon return of the supporting guide bar 1 to the Fig. 2 position.

The spring arm 48 carries a finger 49 for operating a Weighted lever 5I of a conventional switch 52 which is connected by the wiring 3| in series relation with the motor I. Electrically connected contacts 53 of the switch 52 are secured to and operated by the lever 5 I. The finger 49 and the lever 5l have a sliding contact engagement.

Under normal operating conditions of the folding machine the ratchet bar 41 remains in its idle position and the weighted lever 5I remains in circuit closing position (Figs. 2, 3, 4 and 5).

Under abnormal operating conditions of the folding machine the ratchet bar 41 is moved endwise automatically and to the left (looking at Fig. 2), and the finger Il!) shifts the switch lever 5I past its dead center position and to the open circuit position of Fig. 6, where the lever 5I remains until manually returned to the closed circuit position.

Operation When a once folded sheet s is about to pass to the second foldystation, the machine and the safety -device are set as shown in Fig. V5. The switches 32 and 52are -set-in their closed circuit positions, and the-motor l is energized. The perforating blade 8 and .the folding knife 26 are in elevated -positions. The guide supporting bar 1 and the parts supported=thereby are in their perforating position. The ,trip plate 4I is inclined, and the pawl 46 rests on the ratchet bar 41.

'I-he once folded sheet s 4advances below the perforating blade 8 and the folding knife 26 until its forward motion is arrested by the guide clips 6 l(Fig. 1). vAs .the sheet s `moves into engagement with the guide clips 6, the sheet s engages the :trip plate 4| andsWings-it to its vertical position (see Fig. 2 andthe `dotted line position of Fig. V9). .In this swinging movement of the trip plate 4|, the pin 44 raises the pawl 46 to disengage it from the lratchet bar 41. 'Ihe machine and the safety device now have the setting of Figs. 1 and 2, and the vonce folded sheet s is in position and yready fora perforating operation. 'Ihe perforating blade B is now lowered and raised to perforate the sheet s.

The actuating mechanism (see Figs. '7 and 8) for the Ysupporting guide bar 1 now shifts such bar 1, the parts supported thereby, and the once folded perforated sheet s tothe folding position of Fig. 3. In this operation, the sheet s is gripped and advanced by the grippersll (Fig. l), the pawl 46 remains disengaged from the ratchet bar 41, and the switch contacts .53 remain in closed circuit position. The machine is now ready forl the second folding operation. The, setting of the machine and the safety device at this time is shown in Figs. 3 and 8.

In the operation to provide the second fold in the once folded and perforated sheet s, the folding knife 26 is lowered to pass the sheet s into the space between the folding guide bars 3 and thereby initiate the folding operation which is completed by the folding rollers 21 and 28 (see Fig. 2). As the sheet s passes down through the slot between the folding bars 3, the sheet s frees the trip plate 4| and the latter under gravity action is restored to its inclined position (Fig. 4)

The mechanism of Figs. 7 and 8 restores the supporting guide bar 1 and the parte carried thereby to their perforating position of Figs. 2 and 5.

It will now be seen that as long as the sheets s are being fed properly through the machine and to the illustrated second folding station, the safety device is ineffective to open the switch 52 for the purpose of deenergizing the machine motor I. Throughout normal operations of the machine the ratchet bar 41, the spring arm 48, the switch nger 49, and the switch lever 5| are inactive.

In the event any sheet s fails to reach the second folding station and to engage properly the trip plate 4|, the latter and the pawl 46 remain in the position shown in Fig. 5 and in solid lines in Fig. 9. Thus in the next succeeding movement of the guide supporting bar 1 from the perforating position (Fig. 5) to the folding position (Fig. 6), the pawl 46 being in engagement with the ratchet bar 41 drives the latter to the switch operating position shown in Fig. 6. This movement of the ratchet bar 41 causes the finger 49 to shift the switch lever 5| which moves the contacts 53 to the open circuit position of Fig. 6.

'I'hemotor isf-now ',deenergizedfad the-'machine comes to a rest.

When the misfed-sheetzorgsheets*have zbeen removed from the machine, thefmotor driven parts of the machine may bezreset :operation of hand wheels 56 according 4to oonventionalzpracticeato restore the guide supportingibar 1 tonitsperforating position (Figs. 1 andm. "Thisresettingoperation permits vthe springarm tMito :reset the ratchet bar 41 in .its .idlezposition The switch lever 5| is lreturned .manually `to .its .closed circuit position (Fig. 2). '..The machine is `:now lin condition to operategaslongas sheetsv are `being fed properly-and the'safetyidevice now functions as previously explained.

Other suitable and :conventional switches may be used in place yof lthefconventional switch 152. For example, the switch 52.'.may be provided with a spring to retain yieldinglyithe .lever 5| in closed circuit position andv to restore .it automatically'to closed circuit position. With-such type of switch for the safety device vof :this invention, initial starting of the motor r| may be vaccomplished by a conventional push button fswitch, which when closed manually is held. closed. by `a conventional electromagnetic device vconnecte-d in series with the switch of the safety device. .Thus when the safety device switchfisz-placed lin. fopen ycircuit position, the electromagnetic device is deenergized, the push button switchmovesitoopen circuit position and the motor is'deenergized.

The foregoing is to lbeunderstood as illustrative since this invention includes all embodiments and modifications coming within the scope of the appended claims.

I claim:

l. In a sheet folding machine having a motor for driving the machine, a movable guide bar, sheet guide means carried by said bar, means carried by said bar for gripping sheets, means for perforating sheets arrested by said guide means, a folding knife intermediate said guide bar and said perforating means, and means for reciprocating said bar to advance perforated sheets gripped by said gripping means from a sheet perforating station -below said perforating means to a sheet folding station in which the perforations of the perforated sheets uhderly said knife, the improvement comprising means including a pawl and ratchet bar, said pawl being carried by the guide bar, said pawl and said ratchet bar normally being in operative engagement with each other to transmit the sheet advancing movement of said guide bar to said ratchet bar, a device operable by said ratchet bar and adapted to control the motor of said machine, and means responsive to sheets fed into engagement with said guide means for disconnecting said pawl from said ratchet bar.

2. In a sheet folding machine having an electric motor for driving the machine, a folding knife, means for feeding sheets to a position below said knife, and a guide bar having means for arresting and positioning sheets relative to said knife, the improvement comprising a circuit for controlling thek motor and including a switch, means for actuating said switch to open said circuit, and a member for controlling said switch actuating means, said member being supported by said guide bar for free swinging movement and normally in position to free said switch actuating means and to be engaged by the leading edge of a sheet advancing into engagement with said sheet arresting means and shifted by said sheet leading edge to a second position for rendering said switch actuating means inoperative.

3. In a sheet folding machine having a drop knife for folding sheet material, means for feeding sheet material to a position below said knife, a motor for driving said machine including said knife and said feeding means, and means positioned beyond said knife for arresting sheet material passing and positioned below said knife, the improvement comprising means for controlling the operation of said motor, means for actuating said control means to thereby stop said motor, and a freely swinging member for controlling the operation of said actuating means and supported by said arresting means in the path of movement of said sheet material, said member being engageable and movable to an advanced position by the leading edge of sheet material passing below said knife and advancing into engagement with said arresting means for rendering said actuating means inoperative.

4. In a sheet folding machine having a motor for driving the machine, a knife for a first fold, a second knife for a subsequent fold, a perforator adjacent and in advance of said second knife for perforating folded sheets, means foi` feeding folded sheets from said first knife to said perforator, a guide bar having means for positioning sheets relative to said perforatcr and provided With sheet gripping means, means for reciprocating said guide bar relative to said perforator for advancing folded sheets perforated thereby to a S position in which the perforations of the perforated folded sheets underly said second knife, and an electric motor for driving said machine including said knives, said perforator, said feeding means, and said reciprocating means, the improvement comprising a switch for the circuit of said electric motor, a ratchet bar reciprocable to actuate said switch, a pawl mounted to travel with the guide bar and normally disposed to engage a tooth of said ratchet bar and transmit thereto the forward drive of said guide bar to actuate said switch, and a movable member operatively associated with said pawl and mounted to travel with said guide bar, said member being adapted to be engaged and moved by a folded sheet arrested by the sheet positioning means for actuating said pawl to disengage said pawl from said ratchet bar.

LEO R. DICKENSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 164,978 Daniels June 29, 1875 835,235 Adams Nov. 20, 1906 1,713,757 Holt May 21, 1929 1,887,596 Katz Nov. 15, 1932 1,905,099 Jay Apr. 25, 1933 1,916,379 Leland July 4, 1933 

